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About Flash Memory
Both SD memory and Micro SD memory cards may be used for mobile phones, cameras, audio devices such as MP3 players etc, etc, but it is the speed rating of the memory card which is defined in the cards "Class" that counts when deciding if it is a suitable product for your chosen purpose, as well as the manageable memory size as specified by your phone or other device manufacturer!
For example, you could buy the fastest memory product, class 10 and yes it would be great for everything, every purpose, but what a waste of money if all you want is to play a few MP3 tracks through a cheap pair of earphones. On the other hand, if you require memory for an Iphone or similar mobile device, or if you require memory for video recording, it may demand a fast memory speed and a minimum and / or maximum memory capacity.
I personally prefer to use micro SD as they have the versatility of being adaptable by using a SD adaptor to convert to SD size.
All of our memory cards are guaranteed to be full capacity, that is they are the capacity as stated in the specification, less the amount of memory required to program the card usuallyu around 5%, the British public have been so used to being sold rubbish memory cards that they really do not appreciate what true memory capacity is capable of holding. Example, 1GB of memory should hold around 250 MP3 music tracks, so it follows that 8GB will hold 2000 MP3 tracks!